Oil temperature regulator



es, 3,194? A. c. HOFFMAN fi fi CIL 'I'EMPERATURE REGULATOR Filed June 14, 1944 2 Sheets-Sheet 1 Patented Dec. 30, 19 47 1114 TEMPERAE REGULATOR Alien 6. Hofiman, Dayton, @hio, assigncr to United Aircrait Products, line... Dayton, @hio.

a corporation of @hie Application June 5.3, 394d, geriai Ne. fiddlts i This invention relates to oil temperature regulators or like devices used in the cooling or a congealable liquid circulatedunder conditions of Heretofore, in commercially feasible jacketless oil temperature regulators. the oil has been caused to flow either through the cooling passage defined by the core or through an alternative conduit bypassing the oil with respect to thecooling passage; the oil when flowing through the alternative conduit being out of heat exchange relationship with the congealed oil in the core. Accordingly, prior art devices relied upon pressure alone to remove restrictions from the cooling passage, or upona combination of pressure and injection of hot oil directly into the congealed mass. no utilization being made of the warming eflect of the flowing oil in the by-pass. I

An object of the invention is to obtain a quick warm-up of congealed oil in the core by permitting the lay-passing oil toflow in heat exchange relation with the oil in the core.

Another object of the invention is to incorporate a part of the oil by-pass in the core, preferably in the sections of the core nearest the outlet thereof. in such manner that congealed oil in the core is restored to fluidity by heat exchange with the by-passing oil and the pressure required to clear, a path in the core steadily is reduced.

a bias. (ea. ass res) 2 tion when read in connection with the accompanying drawings, wherein:

Fig. l is a view, partly in front elevation and partly in cross section, of an oil temperature regulator embodying the present invention, being takensubstantially along the line l-I of Fig. 2; and 4 Fig. 2 is a view in longitudinal section of the regulator of Fig. 1, the longitudinal air flow tubes being omitted, and being taken substantially along the line 2-2 of Fig. 1.

Referring to the drawings, an oil temperature regulator of the class to which this invention relates comprises a cylindrical shell I l encasing a core made up of a plurality of longitudinally extending spaced partitions l2, and heat exchange tubes I 3 (Fig. 1) flllingthe spaces between the partitions. The ends of the tubes II are expanded to a polygonal shape and occupy a nested relation with respect to each other, the arrangement being such that at the opposite ends of the core the tubes present a closed front while intermediate their ends within the shell II the tubes against the escape of oil from the core. the tube 4 so ends are secured together by a soldering operation. Similarly, the core is rigidly connected to the inner surface of the shell by means constituting a seal "and a bond. The tubes it are open throughout their lengths for the passage there 35 through of a coolant which may be fluid in any form. conventionally, oil temperature regulators for aircraft are disposed in an air stream which passes through the core tubes. cooling the tubes.-

and thereby the surrounding oil in the shell.

and, in effect, forming an integral part of the shell, is a fitting M. The undersurface of fitting "is recessed to provide separate fluid chambers,

k while the upper surface of the flttingis formed 45 with three longitudinally spaced vertical ports, I 5.

i8 and l'|, (see Fig. 2) opening into internal fluid chambers. Port 5 and a fluid chamber l8 overlie= a'longitudinal row of vertical tubular conduits I9, having ends projecting through the shell I l and so which extend inward toward the center of the Secured to the external surface of the shell ll,

regulator core. The inner ends or the tubular conduits i3 terminate in a tank-like enclosure 21 longltudinallydlsposed in the core near the mid "l3 and 22 are combined into a single radial row.

the several elements of which are divided by a fitting rib 24 into groups of approximately equal number communicating with separate fiui'd chamhers-in the fitting. The arrangement is such that fluid entering the fitting ll by way 01' one port II or l3, may flow from the fitting to the tank 2| and then back to the fitting and out the other port I! or IS without entering the cooling passages of the core, although passing in heat exchange relation with the oil therein. Formed as extensions oi the row of tubes [3 and 22. and having their inner ends projecting into the opposite side of the tank 2|, is a row of tubular conduits 25. The conduits 25 lead radially outward to a chamber 23 formed within the shell I I through the cooperation of end sections 21 and a cover plate 28. An opening 23 in the plate 23 communicates the chamber 23 with the core. Thus. oil introduced into the tank 2|, as by the conduits l3, may not only enter the direct return conduits 22 but also may pass through the row of tubular conduits 25 to chamber 26 and from there begin a travel through the cooling passages of the core.

Under the influence of continuously applied pressure the oil may progress through the core back toward the fitting M, and, in so doing, contact successive air flow tubes l3 and be cooled. The partitions l2 serve as baiiles for the oil and preferably have end openings 33 (Fig. 1) similar to the opening 23 to permit the passage of oil therethrough, the openings in adjacent ballles being staggered in such manner as to cause the oil to move in a tortuous path from end to end of the core. The exit from the core is defined by two radial openings 3| and 32, in, the shell H (see Fig. 1), which openings register with .fluid passages 33 and 34 in the fitting M. The passages 33 and 34 communicate with the fitting port I! and are defined by a longitudinal rib 35 which occupies a position astride tubular conduits 22.

The tubular conduits l3 and 22 and the extensions 25 thereof occupy positions substantially in the center of the core,- the channel from which they displacethe' air ilow tubes I3 being closed at the ends by bars 35 having a U shape in cross section. Although the invention is not limited to any partlcular'ma'nner of mounting the tank-like enclosure 2|,thisfl tank preferably has a length coincident with'the length of the core. openings may be provided in the channel bars 36 for the endsofzthe tank 2| or, as shown, the bar at each endoi the core may be made in two sections, theadiacent ends of which abut the top and bottom of the tank. 'The assembly comprising the'ohannel bars 33 and the tank'2l is made a'fixed partof the'core, the elements of the assembly being soldered to'feach other, and to the ends or the adjoining air now tubes II.

In order that the flow-otjthe oil through the regulator may be controlled in accordance with the temperature and viscosity conditions thereof,

there is customarily mounted on the fitting H a manifold head embolism valves committed and 4 arranged to compel the oil to fiow through the 'core, or topermit a flow in lay-passing relation to the core-a by-passing now being initiated when.

the oil is not in need of cooling or when congelation in the core interferes with the flow therethrough in a manner tending objectionably to raise the pressure in the system. Any known.

manifold head for performing these functions may be used in conjunction with the core construction here disclosed. The manifold head illustrated is one disclosed and claimed in a prior patent application by Walter H. Geddes and Philip W. Schanke, Serial No. 514,300, filed December 14, 1943. Briefly described, the head comprlses,a body portion 31 having openings 38 and 33, respectively constituting the regulator inlet and the regulator outlet. To the inlet 38 is connected a line through which heated oil flows under pressure after its passage through the engine. To the outlet 33 is connected a line returning the cooled oil to the reservoir where it is held and withdrawn as required for re-use in the engine. Entering the manifold head by way of opening 3t the oil flows into a chamber 4| and into contact with a thermostat 42 forming a part of an assembly further comprising valves 43 and 4d respectively controlling ports 5 and G8. A spring ill normally holds the thermostat and valve assembly in a position closing the port 45 and opening port 46. Accordingly, the oil in chamber 4| may pass through port 45 to a chamber 48 communicating with outlet 39 .(see Fig. 1). .In response to a rising oil temperature the thermostat 42 operates to withdraw valve 43 from its seat in port 45 and simultaneously to move valve 44 into a position closing port 46. Now the oil in chamber 4| may pass through port 45 and into a chamber #3 overlying and communicating with fitting port it. Thus oil permitted to enter chamber 49 in the manifold head is allowed to continue its flow into controlled by a valve forming part of a thermo- Thus stat assembly 56. Under relatively cool oil temperatures the valve 55 occupies an open position with respect to the port 52 but as the temperature of the oil increases, valve 55 moves to a. seated position in the port and so closes the by-D ss represented by the tubular conduits 22. Chamber 53, wherein the thermostat of assembly 55 is stationed, overlies and communicates with fitting port H which is the outlet from the core. Accordingly, oil discharged from the core passes around the thermostat and causes the valve 55 to remain closed so long as the temperature remains at a predetermined value. Surge pressures arriving at the regulator inlet 33 are dissipated by allowing the valve 44 to move through and beyond the port 46, thereby opening the direct connection between the inlet 33 and outlet 33 irrespective of the temperature oi the oil. Also, the thermostat assembly 56 is adapted to yield to a pressure of predetermined value applied to the face of the.

valve 55. Thus, even though the valve 55 is held closed by the thermostat the attainment of a predetermined pressure inthe tank 2| and in the municating therewith,

an unseatin oithe valve and a consequent open-" ing of the by-pass through the tubular conduits 22. Reverse flow from the outlet chamber 48 to the thermostat chamber 63 is prevented by a check valve 57.

In the operation of the system when the engine is started with oil packed aroundthe air flow tubes It as a result of congelation, flow through the core is obstructed. At the start 01 the circulation of the oil direct fiow between the inlet 38 and outlet 39 takes place through the open port 46, surge pressures being denied access to the core by the closed valve 43. As operation of the engine warms the oil, thermostat 42 responds by closing port 48 and moving valve 43 to open position to permit the oil stream to enter chamber 49 and fitting inlet port l5. Passing through the tubular conduits W to tank 2| the oil finds the easiest path of continued fiow to be back through conduits 22 to fitting port It and into chamber 5| and through the open port 52 to chamber M and the outlet. The flow so established continues until a further rise in oil temperature causes valve 55 to be moved to a position closing port 52. The entire fiuidfiow then -is compelled to pass from tank 2| downward through the tubular conduits 25 to chamber 26 and thence through the opening 29 to the core. There a combination of heat and pressure loosens and expels any remaining congealed oil and reestablishes fiow through the core. It will be understood that in the course of the by-passing flow through conduits i9, tank 2| and conduits 22, the heat of the flowing oil is transmitted to the congealed oil in the core and has a warming, decongealing eifect thereon. Also, a continuous pressure is maintained through the conduits 25 on the oil in the core, attempting to move it to the outlet. Gradually, as first the core section nearest the outlet and then successive sections away from the outlet are decongeaied by the conduction of heat from the conduits l9 and 22, the pressure required to re-establish fiow through the core is reduced until it drops below the value necessary to obtain a relief opening of valve 55. At this point the pressure of the oil in the tank 2| is sufiicient to maintain flow through the tua first one of said conduit means extending from said regulator inlet to said tank-like enclosure, a second one of said conduit bular conduits 25 and through the core of the the passage therethrough of a coolant whereby the temperature of said liquid is modified through heat exchange, a casing enclosing said tube assembly, means defining in conjunction with a portion of said casing a liquid chamber communicating with the interior of said assembly, an outlet from said assembly, means constituting respectively the regulator inlet and the regulator outlet the latter communicating with the outlet from said assembly, a tank-like enclosure within said tube assembly, and a plurality of conduit means in communication with said tank-like enclosure and passing through said assembly without commeans extending from said tank-like enclosure to said assembly inlet, and a third one of said conduit means extending from said tank-like enclosure to said regulator outlet.

2. In an oil temperature regulator or like device for the cooling of a congealable liquid which is heated and circulated under pressure, an assembly of tubes having their medial portions spaced apart permitting a fiow therearound of the liquid to be cooled, said tubes being arranged for the passage therethrough of a coolant whereby the temperature of said liquid is modified through heat exchange, a casing enclosing said tube assembly, means defining in conjunction with a portion of said casing on one side of said assembly a liquid chamber communicating with the interior oi said assembly, an outlet from said assembly, means oppositely disposed with respect to said assembly inlet chamber and constituting respectively the regulator inlet and the regulator outlet the latter communicating with the outlet from, said assembly, a tank-like enclosure mounted within said tube assembly, a first series of tubular conduits interconnecting said regulator inlet and said tank-like enclosure, a second series of tubular conduits interconnecting said regulator outlet and said tank-like enclosure, and a third series of tubular conduits interconnecting said tank-like enclosure and said assembly inlet.

3. An oil temperature regulator or like device according to claim 2, characterized in that said first and second series of tubular conduits are combined into a longitudinal row of conduits, some of which have their one ends in communication with said regulator inlet and the others of which have their corresponding ends in communication with said regulator outlet and all of which conduits have their opposite ends extend-.

ing into said tank-like enclosure, and said third series of tubular conduits projecting from said tank-like enclosure as extensions of said first and second series of conduits.

4. A core construction for oil temperature regulators, comprising an assembly of tubes having their medialportions spaced apart for a flow therearound of the oil, said tubes being arranged for the passage therethrough of a coolant whereby the temperature of the oil is modified'by heat exchang means defining an inlet to said tube assembly at one side thereof, a tank-like enclosure within said tube assembly and forming a part thereof, a first series of tubular conduits extending radially inward in said tube assembly, the inner ends of said conduits terminating within said tank-like enclosure, a second series of conduits having their one ends within said tanklike nclosure and extending radially outward into communication with said tube assembly inlet, and means dividing said first series of tubular conduits into two groups of conduits whereby oil may be delivered to said tank-like enclosure through one group of conduits of said first series and may leave said tank-like enclosure alternatively by way of the other group of conduits of said first series or by way of the conduits of said second series.

5. An oil temperature regulator of the jacketless type, comprising an assembly of heat exchange tubes, a casing surrounding said tube assembly, means including a portion of said casing defining a header chamber communicating with means a 7 8 said tube assembly. an opening in said casing REFERENCES CITED defining an from said tube assembly a tank The following references are of record in the within said tube assembly, and a plurality otindependent conduits passed through said tube asme of this patent sembly and connecting said tank to the ,exterior- -5 UNITED AT S PATENTS of said casing and to said header chamber, said Number Name Date conduits providing inlet means to the tank and 1,992,796 Young 1 Feb 2 1935 by-pass means for oil which by r as n 0! 2,007,590 Baillie July 9' 1935 gelation within the tube assembly is unable to 2,159,468 Young et a1 May 2321939 leave the tank by way of said header chamber. 10 2 2,49 Belalefl etaL m 19 1940 2,288,599 Ramsaur July 7, 1942 ALLAN C. HOFFMAN. 2,406,203 Cruzan et a1 Aug. 20, 1948 

